“Hasta Siempre, Comandante”, or simply “Hasta Siempre”, is a 1965 song by Cuban  composer Carlos Puebla  The song’s lyrics are a reply to revolutionary Che Guevara’s farewell letter to Fidel Castro when he left Cuba, to advance revolutionary struggle in the Congo and later Bolivia where he was executed.

The lyrics recount key moments of the Cuban revolution, describing Che Guevara and his role as a commander.  The title derives from Che’s  well known exhortation “¡Hasta la Victoria Siempre!” (“Until Victory, Always!”). [adapted from Wikipedia)